How to test a microwave magnetron:

Typical microwave magnetron

Use our step-by-step microwave repair guide to learn how to test your magnetron. Once you have diagnosed the problem we have the OEM replacement magnetron that fits your appliance.

NOTE: Before you test this component, make sure your microwave is unplugged, and that you have discharged the capacitor.

There are two tests to conduct in order to determine whether or not a magnetron has become defective. If you receive results other than what are detailed below, you will have to replace your microwave's magnetron. Each test is described for you here:

TEST 1: Locate your magnetron and label each of the wires attached to it so that you know which wires are to be replaced where. Set your ohmmeter to the lowest resistance scale. Take a resistance measurement between each of the magnetron's terminals by touching each probe to one terminal each. Reverse the probes and take a second resistance measurement. Each measurement should read less than one ohm.

TEST 2: Set your ohmmeter to its highest resistance scale. Touch one of the meter's probes to a magnetron terminal. Touch the other probe to the metal magnetron housing. Take special caution to not touch the two probes together. This could result in an inaccurate reading. This test should produce a reading of infinity - indicating an open circuit.

For more information about microwave magnetrons:


CAUTION: Your microwave oven is capable of giving you a serious electrical shock, even when it is unplugged. We strongly suggest you seek the assistance of an appliance repair technician when conducting any microwave oven repair.